Impact of tropical convective activity on monthly temperature variability during nonmonsoon season in the Nepal Himalayas

Surface air temperature, observed in the eastern Nepal Himalayas, showed large intraseasonal and year-to-year variability during the nonmonsoon season. A significant negative correlation was found in the monthly outgoing longwave radiation (OLR) between the area over the Himalayas and tropical areas between 80 and 150 degrees E, which was confirmed by in situ observation data. The correlation was stronger in the months of December, March, and April with different correlative areas in the tropics. From comparison of data observed over 10 years with OLR and global precipitation data, the variability of monthly local surface air temperature in winter was primarily attributed to the indirect effect of convective activities in the tropics that caused a variation in the precipitation/snow cover condition at high elevations.